What is necessary for a rear-projection CRT display to support a 16:9 aspect ratio and be high definition TV (HDTV)-ready?

To support a 16:9 aspect ratio and be considered HDTV-ready, a rear-projection CRT display requires a digital-to-analog (D/A) converter. This component is essential because HD signals are typically transmitted in a digital format, while traditional CRT displays operate using analog technology. The D/A converter’s role is to translate the digital signal into a format that the CRT display can interpret and render correctly, allowing it to display the higher resolution content properly.

In addition to enabling compatibility with digital signals, the D/A converter also ensures that the display can properly convey the necessary detail and color accuracy that is characteristic of high-definition content. Therefore, without this converter, the CRT display would not be able to process HD signals, making it unsuitable for viewing 16:9 content at the required resolution.